Plug-in switch



FIG. 1 is a perspective view of a plug-in switch showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a first side view thereof, the opposite side being a mirror image of the side shown;

FIG. 4 is a first end view thereof; and,

FIG. 5 is a second end view thereof.

The broken line showing of the plug-in switch is for the purpose of illustrating environmental structure and forms no part of the claimed design. 

The ornamental design for a plug-in switch, as shown and described. 